A number of tips to help you purchase an audiometer for your medical practice:
1. Higher-end audiometers are frequently difficult to operate and contain complex functions not appropriate for all medical practices.
2. Speech eudiometry should not be used in audiometers designed for screening purposes. Pure-tone audiometers should test at frequencies of 500 to 6,000 Hz.
3. Standard clinical eudiometry testing is performed over a range of 250 to 8,000 Hz. While not required by OSHA, bone-conduction testing for annual or baseline audiograms can be useful in determining diagnosis in a clinical setting.
4. A good audiometer has a frequency accuracy within 3% for most testing. For some clinical applications, accuracy within 1% is recommended.
5. If the audiometer is being used for clinical testing and diagnosis then it should be at least type 3 as specified by ANSI S2.6-1996. Type 1 is also recommended for clinical environments where a full range of testing criteria must be met.
6. If you are using the audiometer for speech-testing purposes, the audiometer should be designated at least type C.
7. Use half-octave or octave steps if possible for clinical and screening applications. Half-octave frequencies are often used to verify that the subjects hearing level does not change significantly within an octave.
8. Audiometric testing will require a good set of earphones. If used to deliver the signal to the subject then they should include one earphone for each ear.
9. Insert earphones provide a better fit than supra aural earphones when used with an audiometer. These earphones ensure that sounds are being picked up by the correct ear.
10. Free-field testing should not normally be used. However, this testing can provide a good alternative to earphones when testing small children who cannot stand earphones.